package com.heima.kafka.sample;

import org.apache.kafka.clients.consumer.*;
import org.apache.kafka.common.serialization.StringDeserializer;

import java.time.Duration;
import java.util.Collections;
import java.util.Properties;

/**
 * 消费者
 */
public class ConsumerQuickStart {

    public static void main(String[] args) {

        // kafka的配置信息
        Properties props = new Properties();
        // 连接地址
        props.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG, "192.168.200.130:9092");
        // key和value的反序列化器
        props.put(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class.getName());
        props.put(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class.getName());

        // 设置消费者组
        props.put(ConsumerConfig.GROUP_ID_CONFIG, "group1");

        // 手动提交偏移量
        props.put(ConsumerConfig.ENABLE_AUTO_COMMIT_CONFIG, false);

        // 创建消费者对象
        KafkaConsumer<String, String> consumer = new KafkaConsumer<String, String>(props);

        // 订阅主题
        consumer.subscribe(Collections.singletonList("itcast-topic-out"));

        // 同步提交和异步提交偏移量
        try {
            while (true) {
                // 拉取消息
                ConsumerRecords<String, String> consumerRecords = consumer.poll(Duration.ofMillis(1000));
                for (ConsumerRecord<String, String> consumerRecord : consumerRecords) {
                    System.out.println(consumerRecord.key());
                    System.out.println(consumerRecord.value());
                    System.out.println(consumerRecord.offset());
                    System.out.println(consumerRecord.partition());
                }
                // 异步提交偏移量
                consumer.commitAsync();
            }
        } catch (Exception e) {
            e.printStackTrace();
            System.out.println("记录错误的信息：" + e);
        } finally {
            // 同步
            consumer.commitSync();
        }

        /*while (true) {
            // 拉取消息
            ConsumerRecords<String, String> consumerRecords = consumer.poll(Duration.ofMillis(1000));
            for (ConsumerRecord<String, String> consumerRecord : consumerRecords) {
                System.out.println(consumerRecord.key());
                System.out.println(consumerRecord.value());
                System.out.println(consumerRecord.offset());
                System.out.println(consumerRecord.partition());

                *//*try {
                    // 同步提交偏移量
                    consumer.commitSync();
                } catch (CommitFailedException e) {
                    System.out.println("记录提交失败的异常:" + e);
                }*//*
            }

            // 异步的方式提交偏移量
            *//*consumer.commitAsync(new OffsetCommitCallback() {
                @Override
                public void onComplete(Map<TopicPartition, OffsetAndMetadata> map, Exception e) {
                    if(e != null) {
                        System.out.println("记录错误的提交偏移量：" + map + ",异常信息为：" + e);
                    }
                }
            });*//*
        }*/
    }
}
